Concrete is a versatile construction material. For more durable and strong structures, the concrete of high strength is required. To make concrete more strong, pozzolans are added to concrete. Metakaolin ( MK ) is a pozzolana used to achieve the required strength. The present study investigates the characteristics strength of concrete due to partial replacement of cement by MK and addition of polypropylene fibres (PPF). M30 concrete was designed according to BIS guidelines. The investigation was carried out on concrete containing MK and PPF at various proportions of 0%, 7%, 8% and 9% of MK and 0%, 0.2%, 0.5% and 0.8% of PPF. Fly ash (10%) and superplasticizer (0.7%) has been added to improve the workability of concrete. In present study, the results of X-ray diffraction (XRD) analysis of concrete containing metakaolin and fly ash were analysed. Analysis of cement, metakaolin and fly ash was done with XRD. Samples K0, K4, K8 and K12 containing 0%, 7%, 8% and 9% MK (by weight of cement) respectively at the sample age of 1 day were also analysed with XRD.